Difference between revisions of "Phosphatase Subfamily PTC7"

Revision as of 01:04, 11 November 2016

Phosphatase Classification: Fold PPM (PP2C): Superfamily PPM (PP2C): Family PPM (PP2C): Subfamily PTC7

Evolution

The PTC7 subfamily is found throughout eukaryotes. It is single copy in most opisthokonts.

Domain Architecture

PTC7 proteins typically consist of a single structural domain: a PPM-fold phosphatase domain. A PLAT domain is found N-terminal of the phosphatase domain in Monosiga, some algae and scattered other organisms, and Monosiga also encodes an uncertain C-terminal LIM domain.

Functions

Yeast Ptc7p dephosphorylates and activates the mitochondrial hydroxylase Coq7p (Cat5p) and so activates coenzyme Q6 biosynthesis. Ptc7 may reverse the action of the Coq8 kinase (ABC1/YGL119W) (see, e.g. [1]), and in humans, ABC1 kinases ADCK3 and ACDK4 have been implicated in the related coenzyme Q10 biosynthesis [2]. COQ7 is found in most eukaryotes, except plants and excavates [3]. Human COQ7 is also mitochondrial and involved in coenzyme Q10 biosynthesis. It is suggested that the conserved S114 residue in yeast COQ7 is phosphorylated and controls its activity [4], though other studies claim that Coq7p is only phosphorylated on 3 residues in the unconserved N-terminal region [5].

Subcellular localization

Human PPTC7 is reported as a mitochondrial protein by multiple datasets summarized in Mitominer, and knockdown in human cells has an effect on mitochondrial respiration [6], though PPTC7 lacks a mitochondrial targeting signal TargetP 1.1.

References

1. Error fetching PMID 24406904: [He]
2. Error fetching PMID 24270420: [Ashraf]
3. Error fetching PMID 23940037: [Martin-Montalvo13]
4. Error fetching PMID 26497406: [Busso]
5. Error fetching PMID 21812761: [Martin-Montalvo11]
6. Error fetching PMID 24767988: [Lanning]
7. Error fetching PMID 25961505: [Monaghan15]

Technical notes

Accessory PLAT domain is found in a small number of single cellular eukaryotes

The combination of PLAT and PPM domain is found in sparsely, by BLASTing monosiga PTC7, both full sequence and the region containing PLAT and PPM, against eukaryotes NR dataset. domain (1-400). Below are the organisms and their genes that have the domain combination of PLAT and PPM:

• Choanoflagellate: Salpingoeca rosetta (XP_004994085.1)
• Algae: Monoraphidium neglectum (KIY99478.1), Micromonas sp. RCC299 (XP_002499745.1), Bathycoccus prasinos (XP_007509274.1), Ostreococcus tauri (XP_003078617.1), Auxenochlorella protothecoides (XP_011395907.1)
• Cryptomonad: Guillardia theta (XP_005819750.1)
• Fungus: Blastocystis hominis (CBK25361.2)